DIY Redneck LBZ Downpipe [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: DIY Redneck LBZ Downpipe


the4wheeler
12-02-2006, 06:35 PM
http://www.dieselplace.com/forum/garageimage.php?do=full&p=20800&d=1165097178
first off to do it right not every one will have the tools nessary ie: a TIG welder and a Lathe.
but if you want to do redneck style it can be done with a basic MIG welder and grinder and some time

if you do do this you need about a day and you will be destroying your yor cat pipes and downpipe so theres no going back unless you have a extra set sitting around rember that

the olny thing i had to buy for this project was the 4" 90 deg pipe 26 bucks every thing els is provided to you by GM in the way of the SS Cat pipe that we all took off and the lead in portion of SS pipe to the muffler and of course the flange of the stock downpipe

im assuming that we all have allready removed our cats and tailpipes and front pipes.... to git to the down pipe remove the heat shealds off of everything including the big one that sits on top of the turbo ( yes it is a PAIN IN THE @$$! helps to remove the air baffle)
remove the one bolt (14mm i think) its on the bottem of the stock down pipe bolted to the bottem of the engin block if i recall
then take a 12 mm socket or wrench to to the band clap (yes it is a pain to depending on the direction that it was put on
http://www.dieselplace.com/forum/garageimage.php?do=full&p=20807&d=1165100027


remove the band by sliding it down the downpipe then the hole down pipe should slip out and down the side of the trans and out the bottem

TIME to start cutting!

http://www.dieselplace.com/forum/garageimage.php?do=full&p=20803&d=1165097213

you can kinda see the main bend that you will use for the 90 that comes out of the turbo it coems from the front of the cat pipe whrere the "V" band clap was. if you look at the crude drawing you can see you will have to do a "Blogonie cut" (im shure thats not spelled right) to git the clearence aginst the firewall its about 3 1/2 inches from the turbo guess what your using 3 1/2 tube .....

http://www.dieselplace.com/forum/garageimage.php?do=full&p=20806&d=1165099164

every thing is prity basic strate cuts you will have to shape the ends of the pipe a little bit because thay are not purfactly round when the tube was bent . i dont have any meserments to give out so you do need some skill and pachents (SP?) to fit the pipe in but there is room to have some slop. the second bend you will need is about 30 deg. and comes from the "IN" side for the muffler and is the last bend jsut befor it goes when you cut this leve your self some extra on each end if you can , so you have some room to trim and fit . the last peice you will have to cut is the turbo flange on the stock downpipe cut it right at the bottem taper (you can kinda see on the drawing) the taper gives you a nice V (when you mate it to the 90) to lay your beeds in when you weld it up

start by tacking the 90 to the turbo flang yes there will be a gapeing hole at the bottem from the "Blogonie cut" that will have to be filled later.
go fit it on the tuck make shure you can git it in the turbo once you do that then you can go ahad and weld it up DONT USE A LOT IF HEAT the flange can distort go ahad and fit a peice of stainless (from a scrap peice of pipe) in to the bottem of the flange and weld up
http://www.dieselplace.com/forum/garageimage.php?do=full&p=20799&d=1165097169
i would HIGHLEY subjest TIG welding it give you the best results
onceyou got it welded up fit it back on the truck loosle put the band clamp back on so the downpipe wont keep falling off
take your 30deg bend and fit it up make shure it clears.. take off the first part of the downpipe tack the 30 deg pipe to it and refit on the truck weld it once you are happy with the clearences
http://www.dieselplace.com/forum/garageimage.php?do=full&p=20801&d=1165097191
Congras you have your self a basic hi-flowing downpipe from this point you can and what ever size 90 to git you back to a front pipe i used a 4" you can see in the first photo that i flaird out a peice of pipe -trimed off soem of the downpipe that ran long fitted the 90 up and welded every thing up if you do this make shure you can remove the hole down pipe with out it gitting hung up wiht the bottem 90 being welded on ....

its not as pritty as the TTS down pipe (sorry Steve i wont be ordering one i am happy with what i made)
the smother flow of this pipe gits rid of that cool "jet fighter" =( sound in the high RPM's and gives a bit more engin rumble sound pluss its gota flow 10X better than that POS factory down pipe

if you have any questions feal free to ask away
sory for the spelling its kinda bad lol

REMBER this is jsut a a wright up of what one guy did to his truck if you mess up your truck and completly wreck your exhaust atempting to do the same its YOUR FAULT!!!!
o yea this donwpipe is for us guys with the VG turbos

johnmay19
12-02-2006, 09:26 PM
Some nice looking welds there.

irishtornado
12-02-2006, 10:06 PM
Looks really good...wonder if you could buy the pipe and fitting needed at a muffler shop...so you don't have to trash your exhaust....

Al in TN
12-02-2006, 10:20 PM
Once more, nice welding. Here in TN, that be a professional job!!!!!!!!!!

Fingers
12-02-2006, 10:51 PM
Your a man of my own heart there partner. Good job!

dozerboy
12-02-2006, 11:26 PM
X2 very nice

the4wheeler
12-04-2006, 10:40 AM
thanks every one
im shure you could git all the pipe nessary from a shop but i figured why buy exspencive (SP?) SS pipe when GM allready gives it to ya
i did make a turbo flange from a peice of scrap SS figuring i could use it to mock up the parts and still be able to drive my truck
http://www.dieselplace.com/forum/garageimage.php?do=full&p=20804&d=1165097224
but i ended up jsut cutting the stock flange off because it had that nice taper on the one side wich made it easy to fit up to the pipe

Ruben Z
12-04-2006, 11:27 AM
Dude seriously. That’s awesome! But you need to work on that spelling lol.

the4wheeler
12-04-2006, 01:13 PM
Dude seriously. That’s awesome! But you need to work on that spelling lol.

LOL sorry but im afraid thats a lost cause! lol

irishtornado
12-04-2006, 01:20 PM
Interested in making up anymore of these?

smokinLBZ06
12-04-2006, 03:46 PM
Interested in making up anymore of these?

X2

mattydmax
12-04-2006, 10:52 PM
I wouldn't let you check my kids english papers but you can weld on my truck anytime!!!! Good job.

kctay
12-15-2006, 03:26 PM
OMG! :eek:

Wolford
12-15-2006, 06:22 PM
Those welds look good.

the4wheeler
12-15-2006, 06:39 PM
OMG! :eek:


LOL im not quite shure how to respond to that :D



well proably wouldent sell any..... at this time

but would be more than happy to answer any questions on how to build one or provide you all with more pictures